Heat transfer device for corrugator rolls



Aug. 22, 1939. H. B. GREENWOOD HEAT TRANSFEB'DEVICE FOR CORRUGATOR ROLLS 2 Sheets-Sheet 1 Filed Dec. 29, 1957 Aug. 22, 1939. H. B. GREENWOOD HEAT TRANSFER DEVICE FOR CORRUGATOR ROLLS Filed Dec. 29, 1957 2 Sheets-Sheet 2 Q LQW R kn o Patented Aug. 22, 1939 v 2,170,405 v HEA TRANSFER DEVICE FOR ORRUGATOB ROLLS Henry 1;. Greenwood, Glen Arm, Ma, auignor to F. X. Hooper Company, Ina, Glen Arm, MIL, a corporation of Maryland Application December 29, 1937', SerlalNo, 182,220 I 1 Claim. (01. 257- 95) 3 The invention relates to the production of corto the outer surfaces of the rolls and hence to rugated paper and corrugated board of the single the paper. and double-faced variety. It is also an object of the invention to arrange In the production of corrugated paper, which -these heating or heat-absorbing surfaces so as to .5 may either be sold for use in'this form or proprevent coating with a filnrof water. For this 5 vided with a flat facing sheet on one or both sides. purpose they are arranged inwardly from:- i. e., it is regarded as essential to heat the corrugator nearer the axis than, a point of accumulation of rolls between which the straw, as the cheap the condensed water. Such heating or heat-abpaper that is treated in this way is called, is passed sorbing surfaces are most conveniently located on in the corrugating operation; and it is to-the fins or. vanes inside the roll and. connected in 10 heating of these rolls that the invention primarily heat-transferring relation to thewall of the roll. z elates', though it is capable of appiicaion to other The invention also contemplates the provision oils used in presenting the facing sheets, or webs in combination. with heating or heat-absorbing and'in the application of the same.- fins of means for confining the condensed water The prior art and the existingpractice-include to a limited area to prevent the formation of a 15 the-heating of'the corrugator rolls, as aboveioutfilmof water on the fins. The corrugator rolls lined, by means of steam introduced continuously have been provided previously with means for disduring the operation of the rolls in'any suitable charging condensed water. In order not to inmanner, the usual practice being to make the rolls terfere with this operation the fins are, in the UNITED STATES PATENT OFFICE hollow or tubular and introduce the steam to the preferred form, arranged in a helix or are other- 20 chamber or hollow within the roll, and to diswise helically inclined to-the roll axis to cooperate charge the condensed water therefromby means with the discharge means. It is feasible, howof pipes or tubes arranged concentrically with the ever, to effect a different arrangement of these fins axis of the roll. whereby they are entirely independent of any In the heating of the rolls by steam there is a means for collecting the condensed water or its 25 considerable degree of condensation due to the removal.

abstraction of heat from the rolls incident to In each instance, there is means for dischargheating the paper or straw web and also due to lug condensed water and preferably a reservoir the exposure of the heated rolls to the air. The for the same below the main fin surface area.

condensed water which results from this action The fins, on account of their radial extent from 30 presents a considerable obstacle to the efficient the bottom of said reservoirs, are free of any waheating of the cylindrical walls of the rolls and ter film and are exposed todirect contact with and particularly to their outer surfaces where they to the full heating action of the steam; and these contact the paper or straw. This obstacle is in fins, being directly attached to the cylindrical the nature of an insulating effect due to the fact outside walls of the rolls, conduct the heat from 35 that the condensed water forms a film of greater the steam directly to these walls from whence it or less thickness on the inner surface of the roll, passes to the outer surface which contacts the which cannot be eliminated by the usual methods paper or straw. These fins and reservoirs may he of removingcondensed water,the known tendency in any desired arrangement and combined with of the water being to distribute itself by centrifuany suitable means for discharging the condensed 40 gal action and the action of gravity over the enwater. tire inner surface of the roll which, in the absence In the drawings: of this film, would be in direct contact with the Figure 1 is a longitudinal fragmentary sectio hot steam. The insulation thus accomplished is through a single-facet type of corrugating mahighly detrimental to the efficient transfer of heat chine, showing the conventional arrangement of 45 from the steam in the chamber to the paper. corrugating and facer rolls.

An object of the present invention is to provide Figure 2 is a side elevation of a heated corruheating surfaces or heat-absorbing surfaces in gator roll together with the steam supply and the heat-conducting relation to the outer walls of discharge means for the condensed water, the

the rolls, which heat-conducting surfaces are so roll being broken away intermediately to show the 50 arranged as to be substantially free at all times samein longitudinal section on a plane of the roll from this film or coating of condensed water and axis. I in direct contact with the steam, thus giving Figure 3 is an enlarged section taken on the added efficiency in the transfer of the heat from line 3-4 in Figure 2.

the steam content of the chambers within the rolls Figure 4 is a fragmentary section on the same"55 plane as Figure 2 showing a corrugator roll equipped with another form of heat-transfer fln or vane.

Figure 5 is a section similar to Figure 4, showing still another form of heat-conducting vane or fin.

Figure 6 is a section on a reduced scale corresponding to Figure 2, showing a roll equipped with a heating fin or vane differently arranged.

Figure 7 is a section on the line 1-1 in Figure 6.

Referring to the drawings by numerals, each of which is used to indicate the same or similar parts in the different figures, the construction shown in Figure 1 comprises a side frame I on the far side of the machine. It also-includes upper corrugator roll 2, lower corrugator roll 3, presser roll 4 for applying the facing web to the corrugated web, paste rolls 5 and B, paste trough 1, and facing web, heating and transmitting rolls 8 and 9.

The corrugator rolls 2 and 3 are grooved longitudinally at I0 in accordance with the usual practice, and the corrugations of these rolls are meshed at II so that the straw web I2, which is fed to the top of the upper roll 2 and passed around the same downwardly in right-handed rotation and rearwardly between the rolls at ||,is distorted and pressed in the form of corrugations at this point and, passing around the roll 3 in left-handed rotation, is paste-coated by means of the upper pasting roller 5, the facing web I4 being applied at the contact zone of the rolls 3-4 indicated by reference character I5, the finished single-faced web being indicated at l6 and it being understood that the roll-heating device of the invention may, if desired, also be employed in connection with rolls for applying the second facing web or sheet in the production of doublefaced corrugator board. All said rolls are, in accordance with existing practice, made hollow and are steam heated.

The facing web I I which is fed from the right at the bottom of the construction shown in Figure 1 in any suitable manner is passed clockwise to the left and upwardly substantially half way about the heating and transmitting roll 9 and upwardly to the second heating and transmitting roll 8, passing about the right of the same in lefthanded rotation, being passed from the top of this roll to the bottom of pressing roll 4, and being passed upwardly and clockwise about this roll to the contact point I5 where the operationof affixing the facing sheet or web to the corrugated paper takes place as already described.

Figure 2 shows a corrugator roll A grooved or corrugated exteriorly in the usual manner at In and having a shaft I6 secured to the roll at its right-hand end, which shaft is mounted in suitable bearings I! to rotate therein. At its opposite end, the roll has a hollow shaft I8 secured thereto in any suitable manner and mounted to rotate in bearings I9, both sets of bearings being supported on the side frames and I.

The passage or opening 20 within the shaft is connected at 2| to the chamber 22 within the roll A, which represents the corrugator roll construction 2 or 3, Figure 1, to which chamber 22 steam is fed by way of the passage 2|] from a conventional steam joint 24 provided for this purpose and fed by a steam pipe- 25 which carries live steam to chamber 23 in said fitting, which chamber is connected to the passage 29. The steam joint 24 is also provided with a condensed water discharge chamber 26 to which a downwardly disposed discharge pipe 21 is con nected, and this condensed water discharge chamber 26 is connected to chamber 22 within the roll by a pipe 28 which extends through the passage 20 within the shaft I8 and is turned downwardly within the roll, having its intake opening 29 near the bottom of a circular peripheral groove 30 which is shown as near the end of the chamber 22 at the left in Figure 2; i. e., toward the bearing I9, and side frame I. The condensed water may be removed by siphonic action or any suitable type of suction device, this particular arrangement for introducing steam and discharging condensed water by way of the axis of the roll, being known to the art.

An important feature of the invention resides in the provision of the fins or vanes 3| which project inwardly from the wall surface 33' of the roll and of chamber 22 in a radial direction toward the axis of the roll, providing between them a deep storage reservoir 32 for condensed water which leaves the vanes or ribs 3| exposed at all times and free of any water film, the storage chamber 32 between the ribs being of sufficient volume to accommodate the condensed water in contact with the wall surface 33' of the roll at the bottom of reservoir 32, leaving at least four-fifths of the height or depth of the fins or vanes 3| exposed to direct contact with the steam, whereby they serve as conductors for loading the heat abstracted directly from the steam to the outer surface of the roll at 33.

In the form shown, though other arrangement is contemplated, the storage chamber or reservoir 32, being in the form of a helically arranged channel between the ribs or vanes 3|, scrvcs to conduct the condensed water to the circular peripheral groove 30 where it is taken up by the discharge pipe 28 at the depending intake end of the same at 29, the helix being suitably related to the direction of rotation for this purpose. The radius or depth of groove 3|) is preferably a little greater than the radius of the remainder of the chamber 22.

Figure 4 shows the fins or ribs 3| extended and increased as to their heat-absorbing surfaces by means of suitably arrangedplates 34 seated in slots 35 located in the inner faces 36 of the ribs or vanes 3|. These plates are shown as extending helically about the axis along the inside of the roll. The drawing shows a securing means in the form of solder or other strip of metal 31 forced or otherwise inserted in the groove 35 at the side of the base portion of the plate 34. This form also includes storage reservoir 32 which accommodates the condensed water; holding it out of contact with the main portion of the vane surface area, the water occupying but a small volume at the bottomof its reservoir 32.

Figure 5 shows a heat-absorbing fin or vane 3|" having its inwardly-disposed surface 39 inclined to the axis, forming sharp edges 40,'thus eliminating any possibility that the'condensed water may form a film on the inner surfaces of the ribs, the corresponding surfaces being indicated at 39' in Figure 2. The inclined surface 39 pro vides for the projection outwardly into the bottoms 33 of the grooves or reservoirs 32 of any water which may be deposited on the surfaces 39, thus leaving the entire rib under all circumstances, except for the slight area which may be immersed at the base, fully exposed to heating by the action of the steam, giving a consequently more efficient transfer of the heat to portions 40 of the ribs and thence to the surfaces 38 of the rolls. This shaping of the ribs as distinguished from that in Figure 2 is a refinement giving increased exposed surface as well as slightly better clearance of water.

Figures 6 and '7 illustrate still another type of heating device in the form of longitudinally-arranged ribs or fins 45, as best shown in Figure 7. The inner surface 48 of the wall 41 of the roll is provided with shallow peripheral grooves 48 which are connected together by longitudinal grooves 48', which also connect grooves 48 to a relatively deep peripheral groove 49 at the end of the roll or otherwise suitably located from which the condensed water is removed by means of a pipe 28, 29 by siphoning or otherwise, as in Figure 2. The vanes span the grooves 48 and do not obstruct them but deflect the water into the grooves 48 and 48' the over-flow being defiected to the discharge groove 48 and removed. The fins 45 can be combined with any means for collecting and discharging the water, their main purpose being to provide a heat-absorbing surface which is not film-coated, and thus serve to abstract the heat directly from the steam. The fins 45, as shown, are freed of any film of condensed water by centrifugal action; and, being in close contact with the inner surface 48 of the outer wall 41 of the roll, they receive the heat from the steam and transmit it with high efficiency to this wall through which it is conducted directly to the outer surface of the roll, and thus applied to the paper.

The heating device of the invention is capable of application to any and all of the hollow rolls for making corrugated board according to the practice outlined.

The important feature of the invention resides in the provision, on the inside of a hollow steamheated roll of a corrugating machine, of fins which are directly connected in heat-exchanging relation with the outer wall of the roll and project inwardly toward the axis of the roll from the outer wall surface thereof, the roll also being equipped with means for disposing of the condensed water and leading it from the chamber within the roll, whereby only a small quantity of water is normally retained within the roll and this is displaced outwardly from the axis of the roll by the action of centrifugal force, adhesion, and gravity and preferably in a suitable reservoir in the form of one or more depressions in the inner surface of the outer wall of the roll, whereby substantially the entire surface of the fin or fins is free of any water film which might tend to form on the inner surface of the roll as previously constructed. Inthis way the fins are exposed to the direct heating action of the steam and serve to conduct the heat to the main portions of the walls and to the outer surface of the roll by which it is applied to the paper.

,is purely incidental to convenience of arrangement, but this does not interfere with the satisfactory transfer of heat from the steam to the fins; the portion of the area between the fins which is actually occupied by condensed water being at the bases of the fins; i. e., the portion which is outermost in the direction. of the radius,

and the portion of the fins which is normally exposed being at least four-fifths of their radial extent, as indicated by dotted lines W in Figure 2.

I have thus described a preferred and modified form of the invention, the description being specific and in detail in order that the manner of constructing, applying, operating, and using the same may be fully understood; however, the specific terms herein are used descriptively rather than in a limiting sense, the scope of the invention being defined in the claim.

What I claim as new and desire to secure by Letters Patent is:

In a corrugator roll for making corrugated paper having a chamber within the roll and means for introducing steam into said chamber and discharging condensed water therefrom, thin sheet metal vanes in said chamber in heat-conducting relation with the outer surface of the roll and projecting inwardly from the walls of said chamber toward the axis of said roll beyond the area adjacent to the outer walls of the chamber occupied by condensed water and in heatexchanging relation with the steam in said 50 HENRY B. GREENWOOD. 

